Antenna structures onboard telecommunication satellites commonly include rigid reflectors, up to around 2.5 meters diameter, or more complex structures, for example unfurlable wire mesh reflectors up to 9 meters across. The array may operate as a transmit only, a receive only, or as a combined transmit/receive antenna.
Phased array antennas are in general use as compact, stationary structures for the flexible direction of electromagnetic energy for multi-beam, fast reaction tracking radar and telecommunications antennas. They are mechanically static but which can be electronically reconfigured to transmit or receive signals over a defined coverage region. For example ground based satellite terminals use phased arrays for tracking and communicating with satellites in low earth orbit, and flat plate phased array antennas are used for reception of satellite direct to home TV broadcasts.
Phased array antennas are used as an alternative to conventional reflector antennas onboard communications spacecraft. Examples include the Boeing Gapfiller military satellite, which uses fixed (non-deployable) separate receive and transmit X-band arrays (http://www.boeing.com/defense-space/space/bss/factsheets/702/wgs/wgs factsheet.html) and the Boeing Spaceway commercial satellite system, which uses which uses fixed Ka band phased arrays (http://www.boeing.com/ids/allsystemsgo/issues/vol1/num3/story06.html). These antennas are of relatively small aperture and are fixed structures.